28701709 has 4 divisors (see below), whose sum is σ = 28744416. Its totient is φ = 28659004.

The previous prime is 28701703. The next prime is 28701719. The reversal of 28701709 is 90710782.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 28701709 - 2¹¹ = 28699661 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28701703) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 20329 + ... + 21694.

It is an arithmetic number, because the mean of its divisors is an integer number (7186104).

Almost surely, 2^28701709 is an apocalyptic number.

It is an amenable number.

28701709 is a deficient number, since it is larger than the sum of its proper divisors (42707).

28701709 is an equidigital number, since it uses as much as digits as its factorization.

28701709 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42706.

The product of its (nonzero) digits is 7056, while the sum is 34.

The square root of 28701709 is about 5357.3975958482. The cubic root of 28701709 is about 306.1746656850.

The spelling of 28701709 in words is "twenty-eight million, seven hundred one thousand, seven hundred nine".